LS Cable SHS-X500 heatsink/fan

One end of the X500's two heatpipes are embedded (soldered?) in a base that appears to be nickel-plated copper. Starting from the opposite end, about half the length of the heatpipes are fitted with thin rectangular copper fins. The heatpipes are bent into U-shapes so that the fins are positioned about an inch above the base.
The fins have no direct contact with the CPU die;
the heat from the CPU is transferred to the fins by heatpipes alone. Between the base and the fins is a centimeter wide gap. The effect of all this is that back pressure for the airflow through the heatsink
is minimized. The fin depth is also
very short, approximately a centimeter, which means airflow impedance should be minimal.

The design looks promising for use with a quiet, low speed fan, which requires minimal
back pressure and impedance to cool effectively. The main drawback is that a large amount of fin
surface area has been sacrificed, and performance may suffer as a result.

There is about a centimeter of free space beneath the fins, which provides a
clear exhaust path for hot air.
It also provides airflow for the motherboard components around the CPU, which is particularly important for the voltage regulators.

The view from the underside.

The X500 comes with
thermal interface material already applied to the base. A plastic cover protects
the base during shipping, but the square of fairly evenly applied thermal goop on our sample was slightly marked
up on arrival.

Thermal interface material preapplied.

The pre-applied TIM was removed, as all current HS testing at SPCR is done using Arctic Silver Ceramique thermal compound. This gave us a chance to examine the base, which was flat and fairly smooth. The visible machining lines could not be felt by the standard test of running my fingernail across the base.